The Nintendo World Championships (NWC) Gray cartridge for the Nintendo Entertainment System (NES) is highly sought for by video game collectors. The cartridge was first utilized at a Nintendo-sponsored video game tournament in 1990, where players competed in custom-made game cartridges with timed challenges across a variety of titles. Only 90 of these unique cartridges were created, with 26 of them being the rarer gray type given away in a Nintendo Power magazine contest. Because of the limited quantity, as well as the fact that they were not sold in stores, the NWC Gray cartridge is extremely uncommon and precious. Furthermore, the cartridge contains a one-of-a-kind combination of games and gameplay modes that are not available in any other form, which adds to its collectability. The NWC Gray cartridge has been known to fetch tens of thousands of dollars at auction, making it one of the most costly video game collectibles on the market.